Overhead loader



Sept. 25, 1956 H. K. WEBB OVERHEAD LOADER Filed Oct. 7. 1949 is L17 [5is'lg INVENTOR HERBERT K. WEBB BY I ATTORNEYS United States Patent C)OVERHEAD LOADER Herbert K. Webb, Vancouver, British Columbia, CanadaApplication October 7, 1949, Serial No. 120,050

4 Claims. (Cl. 214-131) This invention relates to improvements inhydraulically-operated overhead loaders.

An overhead loader may be attached to any type of power traction unit,such as a bulldozer. These loaders usually consist of a bucket or scooppivotally mounted on the traction unit in such a way that it may belowered at one end of the unit to scoop up the material to be elevatedas the unit moves in that direction. When the bucket or scoop is filled,it is raised upwardly over the traction unit so that it discharges itscontents at the opposite end of the unit. The known loaders of this typeare complicated, extremely heavy, and usually are made up of a largenumber of parts which are subject to a great deal of wear. The hydraulicapparatus for operating these loaders is usually quite complicated andit must be very strong in order to lift the great weight of the loader.

The main purpose of this invention is to provide an overhead loaderwhich includes relatively few parts and which may be suitably braced sothat the weight thereof is considerably less than the known types ofequipment of this nature. This reduces the amount of power necessary tooperate the loader, and a suitable leverage arrangement is employedwhich further reduces the required power. This arrangement makes itpossible considerably to reduce the original cost of this type ofequipment, and the maintenance cost is reduced by the use of fewerwearing parts.

With the above and other objects in view, the present invention consistsessentially of an overhead loader for power traction units havingsuitable hydraulic power supply and controls, which comprises a supportadapted to be mounted on each side of a power traction unit, a yokeextending from side to side of the unit pivotally mounted at its freeends on the supports, said yoke being large enough to extend around atleast one end of the traction unit, a bucket carried by the yokesubstantially midway between its ends, an operating arm projectingupwardly from the yoke at a pivot thereof, a pivotally mounted hydrauliccylinder extending longitudinally of the traction unit, and a ramprojecting from the cylinder pivotally connected to the operating armremote from the yoke pivot, said ram being operated by the hydraulicpower supply and controls of the traction unit to raise the bucket fromone end to the other of said unit, as more fully described in thefollowing specification and illustrated in the accompanying drawings, inwhich:

Figure 1 is a side elevation of the overhead loader in thebucket-loading position,

Figure 2 is a similar view with the bucket in the unloading position,and

Figure 3 is a plan view of the apparatus shown in Figure 1.

Referring to the drawings, is a power traction unit, shown in brokenlines, of any desired type, such as a bulldozer. This unit includes theusual hydraulic power supply and controls for operating hydrauliccylinders, and

2 as these are common to this type of unit, they are not describedherein.

A suitable support 1'4 is mounted on each side of the traction unit inany convenient manner. A yoke 15 is provided, and this yoke extends fromside to side of the unit 10. The yoke is large enough to extend aroundat least one end of the unit when in a substantially horizontal workingposition, as shown in Figures 1 and 3. A bucket or scoop '16 is carriedby the yoke substantially midway between its ends. This bucket may :beremovably or permanently mounted on the yoke. Furthermore, the bucketmay even form part of the yoke. The free ends 17 of the yoke may bepivotally connected directly to the supports 14, oras preferred,inclined arms 18 may be connected to these free ends. These arms projectupwardly and away from the bucket when said yoke is in its normalhorizontal position, and are pivotally mounted at their free ends onpins 19 which are carried by the supports 14.- Thus, the pins 19pivotally support the yoke 15 as the arms 18 are merely extensions ofthe yoke. Actually, each side of the yoke 15 and the arm 18 connectedthereto form a yoke arm having inclined and horizontal portions when thebucket is in its normal working position.

Suitable apparatus may be provided on each side of the traction unit forraising and lowering the bucket, but it is to be understood that, ifdesired, this apparatus may be provided at one side only. It ispreferable to have the raising apparatus at both sides, as shown,although for the sake of clarity, the apparatus for one side only willnow be described, it :being understood that the apparatus at the otherside of the unit is exactly the same.

An operating arm 25 projects upwardly from the yoke at the pivot pin 19thereof. If the yoke arm '18 is used, the operating arm preferably islocated approximately at right angles thereto. This positions theoperating arm at a substantial angle to the vertical. A brace 26 mayextend from the operating arm to the adjacent side of the yoke, and thismay be substantially parallel with the inclined portion 18 of the yokearm, as clearly shown in Figure 1. A hydraulic cylinder 30 is pivotallymounted at 31 on the support 14. This cylinder extends longitudinally ofthe traction unit, and it has a ram 32 projecting outwardly therefromaway from the bucket end of the yoke, and this ram is pivotallyconnected at 33 to the operating arm 25 remote from the pivot pin 19.When the yoke is in its normal horizontal working position, the pivot 33is preferably located above the pivot point 31 of the hydrauliccylinder, while the latter is preferably located above the pivot points19 of the yoke. It.will be noted that the pivot point 31 is closest tothe bucket end of the yoke and the pivot point 19 is the farthest awaytherefrom, while the pivot point 33 is between and above said pivotpoints.

When the yoke 15 is in its normal horizontal working position, thebucket 16 is at the ground level, and the traction unit may be moved toscoop up the material to be loaded into the bucket. The ram 32 may thenbe operated by the hydraulic power supply and controls of the tractionunit. At this time the ram is moved outwardly from the hydrauliccylinder and this moves the operating arm 25 around the pivot 19 toraise the outer end of the yoke and its bucket. The operating armactually acts as a lever during this operation. As the pivot point 33travels in 'an arcuate path, the pivotal mounting of the cylindermaintains the latter and the ram in line with said pivot point. It willbe noted that during the first part of this bucket elevating movement,the ram is pushing in an upward direction. This provides :a maximumamount of lift for the power available or, in other words, it reducesthe amount of power necessary for this operation. When the bucketreaches a point above the a opposite end of the traction unit, itdischarges and the material will drop into :a vehicle or hopper whichmaybe waiting for it, or it may be merely discharged on to the ground.Figure 2 shows the bucket in the discharge position. Although the buckethas been moved to and beyond its highest point, which is directly abovethe pivot point 19, one cylinder, or two, if there is a cylinder at eachside of the traction unit, is used for the entire movement. This is abig advantage over most overhead loaders now in use since these requiretwo cylinders at each side of the traction unit for a similar movement.In order to return the bucket to its loading position, it is onlynecessary to reverse the control apparatus to draw the ram into thecylinder. This moves the outer end of the operating arm back towards itsoriginal position, and this arm, in turn, moves the yoke and the bucketback to the loading position. It will be noted that at this time thecylinder and its ram are tangentially arranged with reference to thearcuate path followed by the pivot point 33 as the latter moves aroundthe pivot pin 19. This makes it much easier to start the bucket intomotion than would otherwise be the case.

While a scoop or bucket has been shown and described in connection withthis apparatus, it'is obvious that it may be removed and an ordinaryblade substituted therefor, in which case the traction unit would beused as an ordinary bulldozer. The hydraulic cylinders would in thiscase be used to raise and lower the blade.

Various modifications may be made in this invention without departingfrom the spirit thereof or the scope of the claims, and, therefore, theexact forms shown are to be taken as illustrative only and not in alimiting sense, and it is desired that only such limitations shall beplaced thereon as are disclosed in the prior art or are set forth in theaccompanying claims. 5

What is claimed is:

1, An overhead loader for power traction units having traction treads onopposite sides thereof and suitable hydraulic power supply and controls,which comprises a support adapted to be mounted on each side of a powertraction unit, a yoke arm pivotally mounted at one end? on each supportand extendi g towards and beyond an end of the unit, the pivots of saidarms being at least as high as the top parts of the traction treads, abucket carried by the free ends of the arms clear of the unit end, ahydraulic cylinder pivotally mounted on one of the supports andextending longitudinal y of the traction unit, the pivot of the cylinderbeing above the yOke arm pivots and closer to the bucket than thelatter, an operating arm permanently rigidly connected to and projectingupwardly from a yoke arm at the pivot thereof and extending towards thecylinder, and a ram projecting from the cylinder away from the bucketend of the yoke arms and pivotally connected to the operating arm abovethe cylinder pivot, said ram being operated by the hydraulic powersupply and controls of the traction unit to raise the bucket from theone end of the unit to a position substantially above the opposite endthereof.

2. An overhead loader for power traction units having traction treads onopposite sides thereof and suitable hydraulic power supply and controls,which comprises a support adapted to be mounted on each side of a powertraction unit, a yoke arm pivotally mounted at one end on each supportand extending towards and beyond an end of the unit, the pivots of saidarms being at least as high as the top parts of the traction treads, abucket carried by the free ends of the arms clear of the unit end, anoperating arm connected to and projecting upwardly from a yoke arm atthe pivot thereof, said operating arm extending towards the bucket endof the yoke arms at a substantial angle to the vertical, a braceextending from the operating arm to the yoke arm to which the latter isconnected, said brace being permanently rigidly connected to both ofsaid arms, a hydraulic cylinder pivotally mounted on one of the supportsand extending longitudinally of the traction unit, the pivot of thecylinder being above the yoke arm pivots, and a ram projecting from thecylinder away from the bucket end of the yoke arms and pivotallyconnected to the operating arm above the cylinder pivot, said cylinderand ram being tangentially arranged with reference to the arcuate pathfollowed by the pivotal connection of the ram with the operating armwhen said connection moves around the pivot of the yoke arm, and saidram being operated by the hydraulic power supply and con trols of thetraction unit to raise the bucket from the one end of the unit to aposition substantially above the opposite end thereof.

3. An overhead loader for power traction units having traction treads onopposite sides thereof and suitable hydraulic power supply and controls,which comprises a support adapted to be mounted on each side of a powertraction unit, a yoke arm pivotally mounted at one end on each supportand extending towards and beyond an end of the unit, the pivots of saidarms being at least as high as the top parts of the traction treads,each yoke arm having a downwardly inc-lined portion from its pivot and ahorizontal portion extending therefrom, .a bucket carried by the freeends of the arms clear of the unit end, an operating arm permanentlyrigidly connected to and projecting upwardly from a yoke armapproximately at right angles to its inclined portion at the pivotthereof, a brace extending from the operating arm to the yoke armsubstantially parallel with the inclined portion of the latter, ahydraulic cylinder pivotally mounted on one of the supports andextending longitudinally of the traction unit, the pivot of the cylinderbeing above the yoke arm pivots, and a ram projecting from the cylinderaway from the bucket end of the yoke arms and pivotally connected to theoperating arm above the cylinder pivot, said cylinder and ram beingtangentially arranged with reference to the arcuate path followed bythe. pivotal connection of the ram with the operating arm when saidconnection moves around the pivot of the yoke arm, and said ram beingoperated by the hydraulic power supply and controls of the traction unitto raise the bucket from the one end of the unit to a positionsubstantially above the opposite end thereof.

- 4. An overhead loader for power. traction units having traction treadson opposite sides thereof and suitable hydraulic power supply andcontrols, which comprises a support adapted to be mounted on each sideof a power traction unit, a yoke arm pivotally mounted at one end oneach support and extending towards and beyond an end of the unit, thepivots of said arms being at least as high as the top parts of thetraction treads, a bucket carried by the free ends of the arms clear ofthe unit end, a hydraulic cylinder pivotally mounted on one of thesupports and extending longitudinally of the traction unit, the pivot ofthe cylinder being above the yoke arm pivots and closer to the bucketthan the latter, an operating arm permanently rigidly connected to andprojecting upwardly at a substantial angle to the vertical from the yokearm at the pivot thereof and extending towards the cylinder, and a rampr jecting from the cylinder away from the bucket end of the yoke armsand pivotally connected to the operating arm above the cylinder pivot,the pivotal connection between the ram and the operating arm beingconsiderably closer to the bucket than the pivots of the yoke. arms,said ram being. operated by the hydraulic power supply and controls ofthe traction unit to raise the bucket from the one end of the unit to aposition substantially above the opposite end thereof.

References Cited in the file of this patent UNITED STATES PATENTS I2,304,672 Bell Dec. 8, 1942 2,427,968 Hoover Sept. 23, 1947 2,518,096Thorne Aug. 8, 1950 2,529,338 Hoover -t Nov. 7, 1950 2,613,006 BradfordOct. 7,1952

